現代社會中，任何一個商用產品具有省電、省錢和高效率就顯得非常重要。RFID的發展歷史已有數十年之久，而且最近這幾年越來越受到許多研究者的青睞、應用範圍也越來越廣如物流業者、醫療、農業、畜牧業…等。RFID主要的架構包含讀取器以及標籤；讀取器以及所有的標籤共享同一無線的頻道。在傳輸資料時，產生了許多資料碰撞的問題，因此標籤反碰撞機制也顯得格外的重要。本篇論文將提出兩套創新的標籤反碰撞演算法，其名稱分別為EAA (Enhanced Anti-collision Algorithm)以及NEAA(New Enhanced Anti-collision Algorithm Based on Counter and Stack)。EAA演算法是基於ABS演算法所提出的另一套演算法。我們將ABS演算法進行大幅度的修改，並且保有ABS演算法既有的優點。EAA演算法利用堆疊、曼徹斯特編碼、與暫存字串可以有效地降低碰撞的發生機率和減少讀取標籤的時間。
NEAA是基於EAA所提出的演算法，NEAA同樣利用堆疊、曼徹斯特編碼、與暫存字串使得碰撞變的具有意義。由於標籤的識別碼為二元數值且具唯一性，NEAA利用此特性使得讀取器在一個timeslot內可以讀取多個標籤。在一般的環境下NEAA的效能趨近於EAA。但是，在非常大量的標籤環境下NEAA將產生更少的碰撞、消耗更少的讀取時間。

For the modern society, it becomes very important to reduce the power consumption, cost and promote efficiency for any commercial products. RFID (Radio Frequency Identification) has been developed for many years and it got much attention from researchers recently as there are lots of applications such as medical, stock, farming, animal husbandry and etc. being used practically in the real world. Owing to the shared wireless channel between tags and reader during communication, the tag collision arbitration is a significant issue for reducing the communication overhead. This thesis presents two novel anti-collision algorithms; one is named as EAA (Enhanced Anti-collision Algorithm) which is based on ABS (Adaptive Binary Splitting) algorithm, the other is named as NEAA (New Enhanced Anti-collision Algorithm Based on Counter and Stack). EAA improves the ABS algorithm, and inherits the advantages of the ABS algorithm. EAA uses counter, stack, and Manchester code to reduce the probability of collision efficiently. Compared to the methods proposed by other researchers, the performance evaluation shows that the proposed EAA uses fewer timeslots for indentifying tags.
NEAA is based on EAA. NEAA uses counter, stack, and Manchester code to make collision become significant. Since the ID (identification) of a tag is a unique binary number, NEAA uses this characteristic to identify lots of tags in a timeslot. In general case, the performance of NEAA approximates to that of EAA. NEAA will cause fewer collisions, and consume fewer timeslots for identifying tags, if the amount of tags is very large.

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